Adjustable carpenter&#39;s square



Nov. 3, 1964 P. N. NELSON 3,154,857

ADJUSTABLE CARPENTERS SQUARE Filed May 28. 1962 INVEN TOR. EE/MIL A!M51. so/v BYWZW ///s ATTO/P/VEYSI United States Patent 3,154,857ADJUSTABLE CARPENTERS SQUARE Permil N. Nelson, Galesburg, lll., assignorto Lynn H. Ewing, Rock Island, Ill. Filed May 28, 1962, Ser. No. 198,3741 Claim. (1. 33-93) My invention relates to a new and useful improvementin an adjustable carpenters square and more particularly to a carpentersright angle square which is capable of being adjusted through a 90 arcto properly prescribed, pre-selected angles.

A principal object of my invention is in the provision in a device ofthis character of means for angularly adjusting a movable element of acarpenters square relative to the fixed right angularly disposed legsthereof for defining with a great degree of accuracy pre-determinedangles therebetween.

A further object of my invention is in the provision in a device of thischaracter of a means for releasably locking the movable angle-definingelement in any preselected position between the fixed right angularlydisposed legs of the carpenters square.

Yet another and equally important object of my invention is in theprovision in a device of this character of a means for readilydetermining the angle described by the movable element of my adjustablecarpenters square.

Other objects will appear hereinafter.

The invention consists in the novel combination and arrangement of partsto be hereinafter described and claimed.

The invention will be best understood by reference to the accompanyingdrawings showing the preferred form of construction, and in which:

FIG. 1 is a plan view of my adjustable carpenters square in its normalor collapsed condition.

FIG. 2 is a rear plan view similar to FIG. 1.

FIG. 3 is a plan view of my improved carpenters square in an adjusted orangle-defining position.

FIG. 4 is a rear view similar to FIG. 3, and

FIG. 5 is a perspective view of my improved carpenters square showing inan adjusted angle-defining position the movable element thereof.

My adjustable carpenters square includes a base leg which is formed inan inverted L-shape in cross section thus providing a depending baseflange 11, and a supporting flange 12. Extending at right angles to thebase leg 10 is a reversed L-shaped perpendicular leg 13. Thisperpendicular leg 13 provides a bottom flange 14 and a verticalextending guide flange 15. The bottom flange 14 of the perpendicular leg13 is fixedly attached to the supporting flange 12 at the vertex 16 ofthe right angle that is defined between the base leg 10 and theperpendicular leg 13.

Pivotally attached at the vertex 16 is a movable angle arm 17. Thisangle arm 17 is formed to correspond to the base leg 16 and as suchdefines an inverted L-shape member in cross section. The angle arm 17provides a base member 18 which extends in the same plane as thedepending base flange 11 of the base leg 10. The angle arm 17 provides asupport member 19 formed to extend in the same horizontal plane as thesupport flange 12 of the base leg 10. By this construction andarrangement of parts, the angle arm 17 may be seated in facial abut-"Ice ment with the underside surface of the base flange 11 and supportflange 12 of the base leg 10 when in a collapsed condition as viewed inFIGS. 1 and 2.

The free end 20 of the angle arm 17 is movable through an are betweenthe base leg 10 and the perpendicular leg 13 and as such is capable ofbisecting the right angle formed between legs 10 and 13, so as to defineany angle therebetween. A positioning rod 21 has one end pivotallyconnected as at 22 to the underside of the support member 19 of theangle arm 17 intermediate the extremities thereof.

The opposite end of the positioning rod 21 carries a threaded stud 23which is adapted to extend through an elongated slot 24 formed in thebottom flange 14 of the perpendicular leg 13. A wing nut 25 is adaptedto be threaded upon the stud 23 so as to releasably latch the same inany position throughout the length of the slot 24.

A triangularly shaped plate 26 is positioned between the base leg 10 andperpendicular leg 13 adjacent the vertex 14 thereof. This plate 26 hasits hypotenuse scored as at 27 to indicate the different angles that maybe prescribed through the right angle formed by the base leg 10 andperpendicular leg 13.

Referring to FIG. 3 I show my carpenters square adjusted to define anapproximate 40 angle between the base element 18 of the angle arm 17 andthe guide flange 15 of the perpendicular leg 13. The threaded stud 23has moved upwardly through the slot 24 and the wing nut 25 has beenthreaded thereon into engagement with the bottom flange 14 so as tolatch the angle arm 17 in this selected angled position.

While I have illustrated and described the preferred form ofconstruction for carrying my invention into effect, this is capable ofvariation and modification without departing from the spirit of theinvention. I, therefore, do not wish to be limited to the precisedetails of construction set forth, but desire to avail myself of suchvariations and modifications as come within the scope of the appendedclaims.

Having thus described my invention, what I claim as new and desire toprotect by Letters Patent is:

An adjustable carpenters square comprising (a) a base leg angularlydisposed with respect to a perpendicular leg,

(b) said base leg providing along one edge an elongated flange dependingtherefrom and adapted to engage an edge of a work piece so as toposition said perpendicular leg at right angles thereto,

(0) an angle arm pivotally connected to the vertex of the angularlydisposed base leg and perpendicular leg and having a collapsed positionand an extended position where it is angularly positioned between saidbase leg and perpendicular leg to describe a pre-selected angletherebetween,

(d) said angle arm providing along one edge thereof an elongated lateralflange extending in a plane perpendicular to said base leg and adaptedfor nesting relation with respect to the lateral flange of said base legwhen said arm is in its collapsed position and for engaging the edge ofa Work piece so as to angularly position said perpendicular leg relativethereto when it is moved angularly between said base and saidperpendicular leg,

(e) a positioning arm pivotally connected at one end to said angle armand slidanly connected to said perpendicular leg for positioning saidangle arm in a pre-selected angled position relative to said base legand said perpendicular leg, and

( means for latching said positioning arm to said perpendicular leg in aselected position for releasably latching said angle arm in apreselected angle position.

UNITED STATES PATENTS Mahan Nov. 10, Staley June 22, Ferguson July 16,Stanwood Ian. 20, Wilkstrom Ian. 29, Sigmon July 29,

